20515570001 has 4 divisors (see below), whose sum is σ = 20519745600. Its totient is φ = 20511394404.

The previous prime is 20515569989. The next prime is 20515570003. The reversal of 20515570001 is 10007551502.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20515570001 - 2³⁴ = 3335700817 is a prime.

It is a super-2 number, since 2×20515570001² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20515570003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2080421 + ... + 2090258.

It is an arithmetic number, because the mean of its divisors is an integer number (5129936400).

Almost surely, 2^20515570001 is an apocalyptic number.

It is an amenable number.

20515570001 is a deficient number, since it is larger than the sum of its proper divisors (4175599).

20515570001 is an equidigital number, since it uses as much as digits as its factorization.

20515570001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4175598.

The product of its (nonzero) digits is 1750, while the sum is 26.

The spelling of 20515570001 in words is "twenty billion, five hundred fifteen million, five hundred seventy thousand, one".